Non-Target Insects and Beneficial Species

Impact of Pesticides on Non-Target Insects and Beneficial Species

Non-target and beneficial species can be impacted by pesticides through direct or indirect routes, such as water contamination and runoff, pesticide residues, and by consuming food that has been sprayed.

A 2014 study published in Chemosphere examined the effects of different pesticides on a common insect predator.

Researchers found that exposure to some pesticides were lethal, while exposure to others led to a decrease in plant feeding time and reduced predation rates.

The seed treatments had zero effect on pest slugs, and instead were bioaccumulated and then transferred through the slugs into their insect predators, impairing or killing >60%.

This resulted in a loss of crop due to a decline in beneficial insect predators and an increase in pest slug population.

Economic Cost

The European Academies' Science Advisory Council (EASAC) estimates global natural pest control to be worth $100 billion annually. Natural pest control is where insects consume pests so that chemicals are not necessary. It focuses on encouraging predatory insects to consume pests, which is a least-toxic approach that is undermined through chemical usage by destroying the balance that exists within a predator-prey relationship.

Non-target insects also act as a food source for animals that bring in a substantial amount of revenue. US citizens spend over $60 billion annually on hunting, fishing and observing wildlife, much of which is dependent on insects as a food source. Researchers have found that there is a steady decline in these insects due to pesticide exposure and an overall decline in biodiversity. It could be concluded then that, as beneficial insect populations decline, their ability to provide ecosystem services will also decline, impacting the available wildlife for hunting, fishing, and observing. The demand for these recreational activities will stay constant while the supply (availability) will decline, causing an increase in dollars spent by US citizens for each year.